Marcela Villa isn’t a big name in health care — but she played a crucial role in the lives of thousands of Medicaid patients in California. Her official title: denial nurse.

Each week, dozens of requests for treatment landed on her desk after preliminary rejections. Her job, with the assistance of a part-time medical director, was to conclusively determine whether the care — from doctor visits to cancer treatment — should be covered under the nation’s health insurance program for low-income Americans.

She was drowning in requests, she said, and felt pressed to uphold most of the denials she saw. “If it was a high-dollar case, they tried to deny it,” Villa said. “I told them you can’t deny it just because it’s going to cost $20,000.”

Villa, 32, did not work for the government. She did not even work for an insurer under contract with the government. She worked for a company now called Agilon Health. Owned by a private equity firm, it’s among the legion of private subcontractors looking to profit from Medicaid patients.

California’s Medicaid program, known as Medi-Cal, has determined that the Long Beach company, which was paid to coordinate care for about 400,000 patients, improperly denied or delayed care for at least 1,400 of them, state officials confirmed. The state Department of Managed Health Care is investigating further.